Photoshop

Objectives:

In this unit we will acquire skills and knowledge with digital image representation and editing using Adobe Photoshop.

Key Concepts in Unit 1 Include:

Digital Imaging:

A digital image is an array or collection of pixel objects. A pixel object stores color data in Red, Green, Blue, and Alpha values.
The dimensions of an image are measured in Width and Height of Pixels
Digital images are usually measured from the Upper Left corner.
The measurements are stored as an ordered pair of (x, y) where x is the width in pixels and y is the height in pixels.
When pixel based images are edited to change the dimension – a loss of data can result. We see this as “graininess” or “pixilation.”
Raw Picture Files (Bitmaps) store each pixel – great large files
Compression types (JPEG, GIF, PNG, TIFF). Stores images in smaller files for web pages, email attachments, small scale printing.
Photoshop and other Graphic Editing Software work in “Layers.” A layer will store a specific collection of Pixels. Layers represent the order in which images are drawn to the screen. The alpha component of a pixel allows the underlying layer pixel colors to “show through”.
Layers shown in sequence over time become animations.
Images must be “rendered” or combined by software into one Layer to be used in other documents (Word, PPT, Web . . .). (The .psd file must be rendered to a .jpg/.gif/.png)

Graphic Design and Artistry: